The objective of this study is to Pediatric venous thromboembolic events are commonly associated with in situ central venous catheters. The risk for severe venous thromboembolism increases if a larger portion of the vessel lumen is occupied by the central venous catheter. A functioning vascular catheter is required when continuous renal replacement therapy is used in critically ill children. Due to the high blood flow required for continuous renal replacement therapy, the external diameter of the catheter needs to be larger than a conventional central venous catheter used for venous access, potentially increasing the risk of venous thromboembolism. However, children on continuous renal replacement therapy often receive systemic anticoagulation to prevent filter clotting, possibly also preventing venous thromboembolism. The frequency of catheter-related venous thromboembolic events in this setting has not been described. Our main objective was to determine the prevalence of catheter-related venous thromboembolism in pediatric continuous renal replacement therapy. Catheter-related venous thromboembolism is a clinically relevant complication of pediatric continuous renal replacement therapy, with a prevalence of 5.7% in our cohort. Clinicians involved in pediatric continuous renal replacement therapy need to be vigilant for symptoms of venous thromboembolisms and initiate appropriate treatment as soon as possible.